[[Set the layout for the frame’s content >> Create your controls, configure them

Question

[[Set the layout for the frame’s content >> Create your controls, configure them, setup any event listeners, and add them to the frame >> set the frame’s size and default window closing behavior (Can use a main method in the class itself to create an instance and display it, or have a separate “test” class to do that.)]]

Create an application with a GUI containing a JButton which you save in an instance variable. Make your application class implement the ActionListener interface and register itself as an ActionListener for the button. Your actionPerformed handler can simply print the event for now.

just this part if possible >>

Add a JSlider to your GUI. JSlider uses the ChangeListener interface for its listeners. Make your application implement ChangeListener and use the value of the slider to set the label text.

Explanation / Answer

Here you go champ...

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

/**
*
* @author Sam
*/
public class TestGUI extends javax.swing.JFrame implements ActionListener, ChangeListener{

    /**
     * Creates new form TestGUI
     */
    public TestGUI() {
        initComponents();
        jButton1.addActionListener(this);
        jSlider1.addChangeListener(this);
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                        
    private void initComponents() {

        jButton1 = new javax.swing.JButton();
        jSlider1 = new javax.swing.JSlider();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jButton1.setText("jButton1");

        jLabel1.setText("jLabel1");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(159, 159, 159)
                .addComponent(jButton1)
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(102, Short.MAX_VALUE)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(jSlider1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(98, 98, 98))
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(jLabel1)
                        .addGap(178, 178, 178))))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(69, 69, 69)
                .addComponent(jButton1)
                .addGap(77, 77, 77)
                .addComponent(jSlider1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 52, Short.MAX_VALUE)
                .addComponent(jLabel1)
                .addGap(38, 38, 38))
        );

        pack();
    }// </editor-fold>                      

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(TestGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(TestGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(TestGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(TestGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new TestGUI().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                   
    private javax.swing.JButton jButton1;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JSlider jSlider1;
    // End of variables declaration                 

    @Override
    public void actionPerformed(ActionEvent e) {
        jLabel1.setText("Button 1 pressed");
    }

    @Override
    public void stateChanged(ChangeEvent e) {
        jLabel1.setText("Slider position changed to " +jSlider1.getValue());
    }
}

Since I use Netbeans, a lot of auto generated codes are added for look and feel. So to make things easy, I have highlighted the portion of code that are relevant and are of your use. Please look into the code and let me know. If you need a simpler program, just let me know, I shall update the code for you.

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